/*
 * ProGuard -- shrinking, optimization, obfuscation, and preverification of Java bytecode.
 *
 * Copyright (c) 2002-2018 GuardSquare NV
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package proguard.classfile.constant;

import proguard.classfile.*;
import proguard.classfile.constant.visitor.ConstantVisitor;
import proguard.classfile.visitor.ClassVisitor;

/**
 * This Constant represents a method handle constant in the constant pool.
 *
 * @author Eric Lafortune
 */
public class MethodTypeConstant extends Constant {
    public int u2descriptorIndex;

    /**
     * An extra field pointing to the java.lang.invoke.MethodType Clazz object. This field is typically filled out by
     * the <code>{@link
     * proguard.classfile.util.ClassReferenceInitializer
     * ClassReferenceInitializer}</code>..
     */
    public Clazz javaLangInvokeMethodTypeClass;

    /**
     * An extra field pointing to the Clazz objects referenced in the descriptor string. This field is filled out by the
     * <code>{@link
     * proguard.classfile.util.ClassReferenceInitializer ClassReferenceInitializer}</code>. References to primitive
     * types are ignored.
     */
    public Clazz[] referencedClasses;

    /**
     * Creates an uninitialized MethodTypeConstant.
     */
    public MethodTypeConstant() {}

    /**
     * Creates a new MethodTypeConstant with the given descriptor index.
     * 
     * @param u2descriptorIndex the index of the descriptor in the constant pool.
     * @param referencedClasses the classes referenced by the descriptor.
     */
    public MethodTypeConstant(int u2descriptorIndex, Clazz[] referencedClasses) {
        this.u2descriptorIndex = u2descriptorIndex;
        this.referencedClasses = referencedClasses;
    }

    /**
     * Returns the descriptor index.
     */
    public int getDescriptorIndex() {
        return u2descriptorIndex;
    }

    /**
     * Returns the type.
     */
    public String getType(Clazz clazz) {
        return clazz.getString(u2descriptorIndex);
    }

    /**
     * Lets the Clazz objects referenced in the descriptor string accept the given visitor.
     */
    public void referencedClassesAccept(ClassVisitor classVisitor) {
        if (referencedClasses != null) {
            for (int index = 0; index < referencedClasses.length; index++) {
                if (referencedClasses[index] != null) {
                    referencedClasses[index].accept(classVisitor);
                }
            }
        }
    }

    // Implementations for Constant.

    public int getTag() {
        return ClassConstants.CONSTANT_MethodType;
    }

    public void accept(Clazz clazz, ConstantVisitor constantVisitor) {
        constantVisitor.visitMethodTypeConstant(clazz, this);
    }
}
